generator, and receive magnetic field signals on the ground using a magnetic antenna
receiving line, and produce the induced electromotive force in the coil. After
amplification, it can be monitored through headphones, the instrument pointer or
other means. With the movement of the receiver coil, the magnitude of the signal will
change. Path detectors are generally using headphones to monitor the signal amplitude.
Depending on the sound curve detected, you can determine the cable path. Detection
methods are mainly trough method and crest method.
●
crest method
test theory as shown.
When conducting path detection, make the magnet coil axis horizontal to the
ground, and slowly move the coil. When the coil is located directly above the wire
and parallel to the cable, the magnetic field lines are perpendicular to the plane of the
coil. The magnetic field lines go through the coil by maximum coupling, so the
induced electromotive force in the coil is the largest, so that you can hear the loudest
in the headphones. Then move the ferrite antenna on both sides. Only part of the
magnetic field lines will be passing through the coil on both sides, which will
generate induced electromotive force, so that you can hear the audio sound the
headphones. With the slow movement of magnetic antenna, the sound gradually
becomes smaller. In the vicinity of the cable, the sound and its position relationship
forms a single peak curve with peaks corresponding to the test position,which is the
specific location of buried cables. Connecting all of the peaks(loudest point) will be
the laid path of the cable.
